Puzzles or games in which a rectangular box or container is divisible into a given number of spaces, and filled with one cube less than the number which would be required to fill the container, are old to the art. The space, which is not occupied by a cube, thus provides a space into which an adjacent cube may be slid, which in turn creates a space having a different location in the container. Initially, the cubes are placed at random, or jumbled; and the object of the game is to manipulate the cubes to a position which will spell words, or arrange the cubes in a numerical sequence. Most of these puzzles have been single tier puzzles, as for example, the first two referenced U.S. patents.
The third referenced U.S. patent is an example of a two tier puzzle in which the faces of the individual cubes are printed or impressed with letters and numerals. The cubes must be arranged in such manner that it is possible to spell certain words and make certain numerical arrangements. Since the cubes cannot be rotated in the container, such a puzzle is limited to a very few possible words and numerical arrangements. The cubes cannot be jumbled in the container at random because the cubes cannot be rotated or tumbled.
The last referenced U.S. patent is an example of a cube puzzle having a preferred embodiment of five cubes in a container with six spaces. If this puzzle is laid on its side, it is a single tier puzzle. Internally, the container is enough larger that it is possible by tilting, tapping and otherwise manipulating the container, to slide, rotate and tumble a cube. As is clearly stated in the patent, there is always an element of chance because the operator or player is never in full control of the cubes, and he may or may not make a cube act in accordance with his desire.
The last two referenced patents teach puzzles which are in closed containers. Once the desired alignment of the cubes has been attained, it is nearly as time consuming to completely disarrange the cubes as it was to align them in their desired game pattern.